Linear low and medium density polyethylene copolymers (LLDPE), and linear high density polyethylene (HDPE) are known materials which are widely commercially available. LLDPE is also described in U.S. Pat. No. 4,076,698 which is incorporated herein by reference. A commercially important use of LLDPE and of HDPE is in making bags which are conventionally prepared from films by blown film extrusion. Because of the availability of polymers having excellent physical properties, such as tensile strength, the trend has been to reduce the gauge of the film used for economic reasons. Such bags even in film gauge of less than 1 mil have generally satisfactory properties but often are difficult to open, particularly with the thinner gauge films. In accordance with this invention, bag opening characeristics can be improved by blending HDPE or LLDPE with aromatic polymers such as polystyrene or poly(para-methylstyrene). It has been found that the aromatic polymer acts unexpectedly as an antiblocking agent and that blocking is one of the factors which contributes to difficulty in opening thin gauge bags.